Some cases of endocarditis putrida (as some German pathologists call it) are attended with nausea, vomiting, and diarrhoea. The frequency with which this form of endocarditis is associated with pneumonia certainly suggests a blood-poison of great intensity. Although it is rarely met with except in septic conditions, it may occur late in severe forms of rheumatic and traumatic endocarditis or when there has been pre-existing suppurative disease of the bones.
The symptoms which attend embolism from detachment of the fibrinous efflorescences upon the valves are due to the arrest of such a plug in an artery whose calibre is too small to admit of its passage. Beyond the obstruction the circulation is arrested; hence results either an infarction or necrosis of the part whose blood-supply is thus shut off. The organ most liable to be the seat of such emboli is the spleen, and after this the kidney and the brain. Hence the occurrence of hemiplegia with aphasia or marked cerebral symptoms in the course of acute endocarditis is indicative of cerebral embolism.
There are no positive subjective symptoms of interstitial endocarditis. There may be palpitation and a sense of uneasiness, sometimes amounting to pain at the præcordial region, with irregularity in the action of the heart, but all of these, when taken together, are not sufficient for a diagnosis. This can be made only from changes in the heart-sounds produced by changes in the valves and valvular orifices.
PHYSICAL SIGNS of exudative endocarditis.—Inspection.—Upon inspection it will sometimes be noticed that the area of the cardiac impulse exceeds the normal—that it is irregular and often tumultuous. As the disease advances, the apex-beat and the impulse grow more indistinct, but never to the same extent or so suddenly as in pericarditis. In children the vessels of the neck exhibit venous stasis far more frequently than in adults.
Palpation.—At the onset of an endocarditis the cardiac impulse is more forceful than normal, and the heart-action is frequently irregular. In some instances the heart thumps violently against the chest-walls. The force of the cardiac impulse varies from day to day. The impulse is stronger when pain is present over the præcordial space. If during the entire course of the disease there is no decrease in the force of the apex-beat, it may be inferred that there is no deficiency in the muscular power of the heart. When acute endocarditis supervenes upon long-standing valvular disease, there will be an alternate increase and diminution in the area and force of the impulse. When the walls of the heart become weakened by subsequent myocarditis, or when the endocardial inflammation is itself very extensive, the force of the apex-beat is diminished. An endocardial thrill is frequently present in acute exudative endocarditis.
Percussion.—The area of cardiac dulness in endocarditis is normal, unless changes at the valvular orifice retard the outflow of blood from the lungs, and then the right-heart cavities become engorged and the area of dulness will extend beyond the normal limits. But it is to be remembered that the increase is always slight, except in those few cases where the heart-cavities are both suddenly and extensively distended with blood or masses of fibrin. Extensive myo- or endocardial inflammation may so weaken the heart-walls that they will dilate, and then percussion will reveal an enlargement in the area of cardiac dulness.
Auscultation.—On auscultation a murmur or murmurs can be heard over the various cardiac orifices. The fact that valvular disease may have previously existed makes it important, at the first visit to a patient who is suffering from acute articular rheumatism, chorea, Bright's disease, etc., to carefully examine the heart. When cardiac hypertrophy exists and valvular disease has pre-existed, it is difficult, if not impossible, to recognize acute exudative endocarditis or to determine the time of its advent if it exist. The most important and constant sign of endocarditis is a systolic murmur, its greatest intensity being over the apex; but this murmur, which is soft and blowing in character, the so-called bellows murmur, may be either ventricular or valvular. In all cases it is due to roughening or thickening of the endocardium. It often changes its point of maximum intensity during the acute period of the disease. It is developed at the onset of the disease, and when one is on the lookout for endocarditis, this will be the first evidence of its occurrence. And yet in some instances no murmur may be present during the entire course of an endocarditis.
A mitral murmur alone occurs in about 50 per cent. of cases of rheumatic endocarditis. It is usually developed early, and before it becomes distinct it is preceded by prolongation of the first sound. This is a transition sound between a normal heart-sound and a murmur. It is a feeble, wavering sound, extending over the slight interval which normally exists between the first and second sounds.
Other changes that are not murmurs, but which frequently precede them, are loud, ringing normal sounds, muffled first sound, feeble first and intensified second sound, doubling of the first sound, roughness of the first sound, and a humming over the right heart.
Complete absence of the heart-sounds is a rare but possible antecedent of an endocardial murmur. A mitral murmur in acute endocarditis is usually audible over a limited area. It is the exception to hear it both in front and at the back. Very frequently it is heard most distinctly over the stomach.